Service manual

9-2013 9. Troubleshooting
3. Measure and verify AC frequency while changing engine rpm to determine if frequency
response matches engine rpm response.
4. Cycle loads to determine if a particular load causes fault: diagnose faulty load as
necessary.
5. Verify balanced loads in 120/240 VAC applications: balance loads within 10 percent line-to-
line as required.
6. Remove connector J1 from the control and re–install, and try to start the generator set:
inspect, repair, or replace the J1 connector pins as necessary.
7. Measure field, quadrature, and main winding resistance: clean the slip rings, replace the
brushes, repair the harness, and replace the rotor or stator as necessary.
8. Measure field, quadrature, and main winding resistance to ground: clean the slip rings,
replace the brushes, repair the harness, and replace the rotor or stator as necessary.
9. Measure field, quadrature, and main winding resistance to each other: clean the slip rings,
replace the brushes, repair the harness, and replace the rotor or stator as necessary.
10. Check the alignment of the brushes to the slip rings.
9.16 Undervoltage - Fault Code 13
Logic: AC voltage 240 line-to-line less than 216 VAC for 5 continuous seconds
Possible Causes: generator set loads, wire connections, windings
Diagnosis & Repair:
1. Verify that the Last Fault is FC 13: Yes, continue diagnosis; No, troubleshoot actual last
fault.
2. Measure and verify AC voltage at the customer connection block and at pins J1-34 and J1-
35.
3. Measure and verify AC frequency while changing engine rpm to determine if frequency
response matches engine rpm response.
4. Cycle loads to determine if a particular load will cause fault: diagnose faulty load as
necessary.
5. Verify balanced loads in 120/240 VAC applications: balance loads within 10 percent line-to-
line as required.
6. Remove connector J1 from the control and re–install it, and try to start the generator set:
inspect, repair, or replace J1 connector pins as necessary.
7. Measure field, quadrature and main winding resistance: clean the slip rings, replace the
brushes, repair the harness, and replace the rotor or stator as necessary.
8. Measure field, quadrature, and main winding resistance to ground: clean the slip rings,
replace the brushes, repair the harness, and replace the rotor or stator as necessary.
9. Measure field, quadrature, and main winding resistance to each other: clean the slip rings,
replace the brushes, repair the harness, and replace the rotor or stator as necessary.
10. Check brush alignment:
a. Inspect brush wear on the slip rings and verify brush misalignment is toward the
windings.
A030A239 (Issue 10) 93